Irradiation of the object gives rise to scattered radiation, which has a strong effect on the detectability of details in the acquired images. Scattering leads to the reduction in contrast, densitometric imprecision and deterioration of image sharpness. Standard methods of treating the effects of scattered radiation usually directed towards reduction of the intensity of scattered radiation which reaches the image detector (Sorenson, J. A., and Niklason, L. T., 1988, Progress in Medical Imaging, edited by V. L. Newhouse (New York: Springer), pp. 159-184). In many instances implementation of such methods can lead to increase in the dose (by a factor of three or more) and in the noise of the acquired image.
Standard methods solve the task of reducing the effects of scatter in primary image by means of anti-scatter grids, air gaps and beam collimation. These approaches reduce the scatter component of total signal at the detector. However, they do not totally remove it, and they do not affect the veiling glare component directly. Also, the use of anti-scatter grids or air gaps leads to significant increase of the dose (patient exposure)(Sorenson, J. A., and Niklason, L. T., 1988, Progress in Medical Imaging, edited by V. L. Newhouse (New York: Springer), pp. 159-184).
Compensation of the scatter effects can be facilitated by use of computerized image processors connected to an image detector—such as in digital radiographic and fluoroscopic systems (Maher, K. P., and Malone, J. F., 1986, Contemp. Phys., 27, 533). Methods developed so far usually involve an estimation of scattered radiation field and its subtraction from the original image (Love. L. A., and Kruger, R. A., 1987, Medical Physics, 14, 178).
The method, most closely related to this claim, is the method of digital image correction (Patent No EP2120040A1, published 18 Nov. 2009), acquired by means of electromagnetic radiation, including X-ray radiation, which was converted into electric signal and sent to digital imaging device, which includes pyramidal (Laplacian pyramid) decomposition of initial digital image into detailed (high-frequency band) images and approximation (low-frequency band) images, removal of scattered radiation in the approximating part of the images, enhancing the contrast in the detailed part of the images, re-composition of processed approximation and detailed images, which followed by reconstruction and generation of the resulting image.
The drawback of the abovementioned method is that it doesn't provide the possibility of correction of amplitude and frequency properties of the image, noise reduction, removal of effects of scatter and correction of dynamic range of the image in accordance with dynamic range of the output device.